<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        //设置变量接收用户输入年份
        let grade = +prompt('输入你的成绩')
        //判断成绩
        if (grade === 100) {
            alert('🐂')
        }
        else if (grade > 90 && grade <= 99) {
            alert('拉')
        }
        else if (grade > 70 && grade <= 90) {
            alert('有点拉')
        } else if (grade > 60 && grade <= 70) {
            alert('真的拉')
        } else {
            alert('确实拉')
        }

    </script>
</body>

</html>